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The concepts of automation trust and dependence have often been viewed as closely related and on occasion, have been conflated in the research community. Yet, trust is a cognitive attitude and dependence is a behavioural measure, so it is unsurprising that different factors can affect the two. Here, we review the literature on the correlation between trust and dependence. On average, this correlation across people was quite low, suggesting that people who are more trusting of automation do not necessarily depend upon it more. Separately, we examined experiments that explicitly manipulated the reliability of automation, finding that higher automation reliability increased trust ratings twice as fast as dependence behaviours. This review provides novel quantitative evidence that the two constructs are not strongly correlated. Implications of this work, including potential moderating variables, contexts where trust is still relevant, and considerations of trust measurement, are discussed.

In a dynamic decision-making task simulating basic ship movements, participants attempted, through a series of actions, to elicit and identify which one of six other ships was exhibiting either of two hostile behaviors. A high-performing, although imperfect, automated attention aid was introduced. It visually highlighted the ship categorized by an algorithm as the most likely to be hostile. Half of participants also received automation transparency in the form of a statement about why the hostile ship was highlighted. Results indicated that while the aid's advice was often complied with and hence led to higher accuracy with a shorter response time, detection was still suboptimal. Additionally, transparency had limited impacts on all aspects of performance. Implications for detection of hostile intentions and the challenges of supporting dynamic decision making are discussed., (© 2023. The Author(s).)

Objective: Three experiments sought to understand performance limitations in controlling a ship attempting to meet another moving ship that approached from various trajectories. The influence of uncertainty, resulting from occasional unpredictable delays in one's own movement, was examined., Background: Cognitive elements of rendezvous have been little studied. Related work such as the planning fallacy and bias toward underestimating time-to-contact imply a tendency toward late arrival at a rendezvous., Methods: In a simplified simulation, participants controlled the speed and/or heading of their own ship once per scenario to try to rendezvous with another ship. Forty-five scenarios of approximately 30 s were conducted with different starting geometries and, in two of three experiments, with different frequencies and lengths of the unexpected delays., Results: Perfect rendezvous were hard to obtain, with a general tendency to arrive late and pass behind the target vessel, although this was dependent on the angle of approach and relative speed. When occasional delays were introduced, less frequent but longer delays disrupted performance more than shorter but more frequent delays. Where delays were possible, but no delay occurred, there was no longer evidence of a general tendency to more frequently pass behind the target ship. Additionally, people did not wait to see if the unpredictable delays would occur before executing a course of action. Different control strategies were deployed and dual axis control was preferred., Conclusions: The tendency to arrive late and the influence of the possibility of uncertain delays are discussed in relationship to control strategies.

Objective: The ability of people to infer intentions from movement of other vessels was investigated. Across three levels of variability in movements in the path of computer-controlled ships, participants attempted to determine which entity was hostile., Background: Detection of hostile intentions through spatial movements of vessels is important in an array of real-world scenarios. This experiment sought to determine baseline abilities of humans to do so., Methods: Participants selected a discrete movement direction of their ship. Six other ships' locations then updated. A single entity displayed one of two hostile behaviors: shadowing, which involved mirroring the participant's vessel's movements; and hunting, which involved closing in on the participant's vessel. Trials allowed up to 35 moves before identifying the hostile ship and its behavior. Uncertainty was introduced through adding variability to ships' movements such that their path was 0%, 25%, or 50% random., Results: Even with no variability in the ships' movements, accurate detection was low, identifying the hostile entity about 60% of the time. Variability in the paths decreased detection. Detection of hunting was strongly degraded by distance between ownship and the hostile ship, but shadowing was not. Strategies employing different directions of movement across the trial, but also featuring some runs of consecutive movements, facilitated detection., Conclusions: Early identification of threats based on movement characteristics alone is likely to be difficult, but particularly so when adversaries employ some level of uncertainty to mask their intentions. These findings highlight the need to develop decision aids to support human performance.

Previous research suggests people struggle to detect a series of movements that might imply hostile intentions of a vessel, yet this ability is crucial in many real world Naval scenarios. To investigate possible mechanisms for improving performance, participants engaged in a simple, simulated ship movement task. One of two hostile behaviors were present in one of the vessels: Shadowing-mirroring the participant's vessel's movements; and Hunting-closing in on the participant's vessel. In the first experiment, history trails, showing the previous nine positions of each ship connected by a line, were introduced as a potential diagnostic aid. In a second experiment, the number of computer-controlled ships on the screen also varied. Smaller set size improved detection performance. History trails also consistently improved detection performance for both behaviors, although still falling well short of optimal, even with the smaller set size. These findings suggest that working memory plays a critical role in performance on this dynamic decision making task, and the constraints of working memory capacity can be decreased through a simple visual aid and an overall reduction in the number of objects being tracked. The implications for the detection of hostile intentions are discussed., (© 2022. The Author(s).)

Purpose: To summarize results of a Clinical Practice Statement on radiation therapy for stage II-III rectal cancer, which addressed appropriate customization of (neo)adjuvant radiation therapy and use of non-surgical therapy for patients who are inoperable or refuse abdominoperineal resection., Methods and Materials: The RAND/University of California, Los Angeles, Appropriateness Method was applied to combine current evidence with multidisciplinary expert opinion. A systematic literature review was conducted and used by the expert panel to rate appropriateness of radiation therapy options for different clinical scenarios. Treatments were categorized by median rating as Appropriate, May Be Appropriate, or Rarely Appropriate., Results: In the neoadjuvant setting, chemoradiation was rated Appropriate and the ratings indicated short-course radiation therapy, chemotherapy alone, and no neoadjuvant therapy are potential options in selected patients. However, neoadjuvant endorectal brachytherapy was rated Rarely Appropriate. For adjuvant therapy, chemoradiation (plus ≥4 months of chemotherapy) was rated Appropriate and chemotherapy alone May Be Appropriate for most scenarios. For medically inoperable patients, definitive external beam radiation therapy and chemotherapy alone were rated May Be Appropriate, whereas endorectal brachytherapy and chemoradiation plus endorectal brachytherapy were possible approaches for some scenarios. The last option, definitive chemoradiation, was rated Appropriate to May Be Appropriate based on performance status. Finally, for patients with low-lying tumors refusing abdominoperineal resection, definitive chemoradiation alone, chemoradiation plus endorectal brachytherapy, and chemoradiation plus external beam radiation therapy were all rated Appropriate., Conclusions: This Clinical Practice Statement demonstrated the central role of radiation therapy in stage II-III rectal cancer management and evaluated ways to better individualize its use in the neoadjuvant, adjuvant, and definitive settings. Ongoing trials may clarify areas of continuing uncertainty and allow further customization., (Copyright © 2015 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.)

A precision microwave effective linewidth measurement technique for magnetic samples has been developed. The measurement utilizes a high-Q cylindrical cavity that contains the sample of interest, a highly stable and programable static magnetic field source, a computer controlled network analyzer for cavity center frequency omega c and quality factor Qc determinations, and the standard metrological substitution ABA method for accurate relative omega c and Qc measurements. Sequential long term ABA measurements show that the time and temperature drifts and random errors are the dominant sources of error, with uncertainties in omega c/2pi and Qc in the range of 50 kHz and 25, respectively. The ABA method is applied to eliminate these drifts and minimize the random errors. For measurements over 25 ABA cycles, accuracy is improved to 0.14 kHz for omega c/2pi and 3 for Qc. The temperature variation over a single ABA cycle is generally on the order of 10(-3)-10(-5) degrees C and there is no need for any further temperature stabilization or correction measures. The overall uncertainty in the 10 GHz effective linewidth determinations for a 3 mm diam, 0.5 mm thick polycrystalline yttrium iron garnet (YIG) disk is 0.15 Oe or less, well below the intrinsic single crystal YIG linewidth. This represents a factor of 10 improvement in measurement accuracy over previous work.

The longitudinal magneto-optical Kerr effect is used to obtain a calibrated measure of the dynamic magnetization response over the ferromagnetic resonance (FMR) profile for in-plane magnetized Permalloy films excited with high power in-plane transverse microwave fields at 1.25 to 3.75 GHz and in-plane precession angles up to about 20 degrees. The data provide a profound demonstration of the Suhl threshold effect for parametric spin wave generation for angles above about 14 degrees, the magnetization precession lock-up just above threshold, and the complicated response over the full FMR profile at very high powers.

Fermi-Pasta-Ulam recurrence through soliton dynamics has been realized. The experiment used a magnetic film strip-based active feedback ring. At some ring gain level, a wide spin wave pulse is self-generated in the ring. As the pulse circulates, it separates into two envelop solitons with different speeds. When the fast soliton catches up and collides with the slow soliton, the initial wide pulse is perfectly reconstructed. The repetition of this process leads to periodic recurrences of the initial pulse.

The random generation of coherent solitary waves from incoherent waves in a medium with an instantaneous nonlinearity has been observed. One excites a propagating incoherent spin wave packet in a magnetic film strip and observes the random appearance of solitary wave pulses. These pulses are as coherent as traditional solitary waves, but with random timing and a random peak amplitude.

The manifestation of fractals in soliton dynamics has been observed for the first time. The experiment utilized self-generated spin-wave envelope solitons in a magnetic film based active feedback ring. At high ring gain, the soliton that circulates in the ring breathes in a fractal pattern. The corresponding power frequency spectrum shows a comb structure, with each peak in the comb having its own comb, and so on, to finer and finer scales.

The chaotic self-generation of short solitary spin wave pulses has been observed for the first time. The pulses were produced from parametrically excited spin waves in an yttrium-iron-garnet film in an active feedback ring under conditions where both three-wave and four-wave parametric processes were allowed. The power-frequency spectrum was broadband and chaotic.

The generation of dark spin wave envelope soliton trains from a continuous wave input signal due to spontaneous modulational instability has been observed for the first time. The dark soliton trains were formed from high dispersion dipole-exchange spin waves propagated in a thin yttrium iron garnet film with pinned surface spins at frequencies situated near the dipole gaps in the dipole-exchange spin wave spectrum. Dark and bright soliton trains were generated for one and the same film through placement of the input carrier frequency in regions of negative and positive dispersion, respectively. Two unreported effects in soliton dynamics, hysteresis and period doubling, were also observed.

Extremely narrow 2 ns wide microwave pulses are generated from nonlinear magnetostatic surface waves in yttrium iron garnet films. The shortest output pulse with the highest amplitude is achieved for input power levels of about 300 mW and a carrier frequency below 3.3 GHz. The results are explained within the model based on dipole exchange spin wave modes involved in three magnon processes. The characteristic time for these processes to develop, as estimated from the smallest fall time of output pulse, is 1 ns. The relevant modes are verified by Brillouin light scattering.

The self-generation of single, fundamental, stable, spin-wave-envelope black and gray dark solitons has been realized for the first time. These solitons were generated from microwave magnetostatic surface waves (MSSWs) propagated in an in-plane magnetized yttrium iron garnet film MSSW delay line in a resonant ring. These fundamental dark solitons were made possible by a new and general filtering technique for a high gain nonlinear resonant ring. The amplitude and phase profiles together with the power spectra of the self-generated microwave pulses confirm their fundamental dark soliton nature.